Process for the alteration of egg white



Patented Sept. 15, 1936' Q UNITED STATES PATENT OFFICE PROCESS FOR THEALTERATION EGG WHITE Arnold K. Balls, Washington, D. 0., and Theodore L.Swanson, Chevy Chase, Md, dedicated to the free use of the Public of theUnited States oi. America No Drawing. Application. March 6, 1934,

Serial No. 714,277

3 Claims. (Cl. 99-210) (Granted under the act of March 3, 1883, as

- amended April 30, 1928; 370 0. G. 757) This application is made underthe act of to thin white. We have found that this may be March 3, 1883,as amended by the act of April accomplished by activating the trypsinalready 30, 1928, and the invention herein described, if present in theegg white. To this end any patented, may be manufactured and used by orpreparation containing enterokinase may be 5 for the Government forgovernmental purposes mixed with the egg white. We have usedenterowithout the payment to us of any royalty therekinase prepared fromthe intestines of pigs by on. the published methods.

Wehereby dedicate the invention herein dey In order to properly gaugethe amount of enscribed to the free use of the public in theterriterokinase to be added, one should take into acm tory of the UnitedStates of America to take count the amount of inhibitor occurringnatureffect upon the granting of a patent to us. ally in the egg whites,the temperature at which This invention relates to the alteration ofthick they will be kept for digestion, and the time in egg white to thinegg white. The whites of birds which the digestion shall take place. Byineggs when fresh consist of a thin, easily fluid porcreasing thetemperature or the amount of kition, and a thick and viscid portion.These pornase, the digestion is accelerated. At tempera- 15 tions may bemore or less separated by a coarse tures below 25 C. the digestionisslow, at temscreen, which retains the thick white, and allows peraturesabove 40 C. there is danger of destroythe thin white to flow through. Inthe normal ing the trypsin, at temperatures above 55 C., process ofstoring eggs the thin white increases there is danger of coagulating theegg proteins. in amount while the thick white decreases. Temperaturesbetween 30 and 40 C. are recom- In certain industries, however, the thinwhite mended. Occasional or very slow agitation is is more desirablethan the thick white. This is of advantage. true of the industry ofdrying egg white, where Under these conditions we have found that for itis known that the thin white dries more readmost egg whites the amountof enterokinase usuily, is more easily handled in the drier, and givesally present in one part by weight of the dried a more desirableproduct, in that it is more comintestinal mucosa of the pig issufficient to actipletely soluble in water than the dried whole vatethetrypsin of two thousand parts of whole white. In the industry it iscustomary to allow egg whiteto the extent that the thick white is thewhole egg white to stand for several days bepractically all digested inone day or less. (It is fore drying it, in order that the change fromusually advisable to screen out or otherwise septhick to thin white-mayfirst take place. arate particles of undigested membranes from We havefound that the change from thick to the digested mixture.) thin white isa proteolysis, whereby mucin and Both material and time may be saved,however,

probably other proteins of the egg are partly hyby first separating thethin from the thick egg drolyzed by the proteolytic ferments which occurwhite, and treating only the latter with the ki- 35 normally in eggs. Wehave found that one fernase. This method usually requires less than mentwhich is responsible for the hydrolysis of half the kinaseneeded for theentire egg white, thick white is trypsin. The tryptic action doesbecause much of the trypticinhibitor has been 40 not. progress withoutlimit, however, because removed in the thin white.

there is present in thin white an inhibitory sub- We have also foundthat it is possible to substance which retards the breakdown of 'theprostitute certain chemicals for the enterokinase in tein. the aboveprocess, such substances being ben- We have further found that thetrypsin present zoyl derivatives of the amino acids and peptides.

in normal egg white is largely in an inactive or We particularlyrecommend benzoyl glycine for an inhibited condition, and for thisreason the this purpose, and use it in place of enterokinase naturalbreakdown of the thick white proceeds in the amount of one part ofbenzoyl glycine to slowly. five thousand parts of egg white by weight,but

It is desirable sometimes, for instance in the it is understood thatthis amount may vary with industry of manufacturing dried egg products,to the eggs.

accelerate the speed of the breakdown from thick While it is possible touse the activators here described in the form of solid preparations, itis more convenient to use a solution in water, containing in the case ofwater insoluble preparations, enough alkali to dissolve them.

Having fully disclosed our invention, we claim:

1. The process of thinning egg white which comprises mixing with theeggwhite a. substance containing enterokinase at a temperature notexceeding 40 C.

2. The process of thinning egg white which comprises mixing a. substancecontaining enterokinase with the egg white at a. temperature between 25C. and 40 C.

3. In the process 01' manufacturing dried egg white the step of mixingenterokinase with the egg white at a temperature not exceeding 40 C.

ARNOLD K. BALLS. THEODORE L. SWENSON.

